Unrelenting heat wave bakes half the U.S.; 30 dead

Hollie Kuznicki of Denver, Colo. plays beneath water being sprayed by a fire truck at the Sedgwick County Zoo in Wichita, Kan. on Friday, July 6, 2012. The National Weather Service reported late Thursday that the record-breaking heat that has baked the nation's midsection for several days was slowly moving into the mid-Atlantic states and Northeast. (AP Photo by Travis Heying/The Wichita Eagle)